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Climate and Average Weather Year Round in Ärla Sweden

In Ärla, the summers are comfortable and partly cloudy and the winters are long, freezing, snowy, and overcast. Over the course of the year, the temperature typically varies from 20°F to 72°F and is rarely below 2°F or above 82°F.

Based on the tourism score, the best time of year to visit Ärla for warm-weather activities is from late June to mid August.

Climate in Ärla

freezingvery coldcoldcoolcomfortablecoolcoldvery coldJanFebMarAprMayJunJulAugSepOctNovDecNowNow57%57%23%23%overcastclearprecipitation: 2.7 inprecipitation: 2.7 in0.8 in0.8 inmuggy: 1%muggy: 1%0%0%drydrytourism score: 6.6tourism score: 6.60.00.0
Ärla weather by month. Click on each chart for more information.

The warm season lasts for 3.2 months, from May 28 to September 4, with an average daily high temperature above 63°F. The hottest month of the year in Ärla is July, with an average high of 71°F and low of 54°F.

The cold season lasts for 4.0 months, from November 17 to March 15, with an average daily high temperature below 38°F. The coldest month of the year in Ärla is January, with an average low of 22°F and high of 30°F.

Average High and Low Temperature in Ärla

Average High and Low Temperature in ÄrlawarmcoldcoldJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FFeb 830°FFeb 830°FJul 2072°FJul 2072°F20°F20°F54°F54°FMay 2863°FMay 2863°FSep 463°FSep 463°FNov 1738°FNov 1738°FMar 1538°FMar 1538°F45°F45°F47°F47°F30°F30°F25°F25°FNowNow
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.
AverageJanFebMarAprMayJunJulAugSepOctNovDec
High 30°F32°F39°F50°F60°F66°F71°F69°F60°F49°F39°F33°F
Temp. 26°F26°F32°F41°F52°F59°F64°F61°F53°F44°F35°F29°F
Low 22°F21°F26°F33°F41°F49°F54°F52°F45°F38°F31°F24°F

The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.

Average Hourly Temperature in Ärla

Average Hourly Temperature in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMNowNowfreezingfreezingvery coldvery coldcoldcoldcoolcomfortable
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.

Haines, Alaska, United States (4,115 miles away); Terrace, Canada (4,347 miles); and Revelstoke, Canada (4,414 miles) are the far-away foreign places with temperatures most similar to Ärla (view comparison).

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In Ärla, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.

The clearer part of the year in Ärla begins around April 4 and lasts for 6.0 months, ending around October 5.

The clearest month of the year in Ärla is July, during which on average the sky is clear, mostly clear, or partly cloudy 55% of the time.

The cloudier part of the year begins around October 5 and lasts for 6.0 months, ending around April 4.

The cloudiest month of the year in Ärla is November, during which on average the sky is overcast or mostly cloudy 76% of the time.

Cloud Cover Categories in Ärla

Cloud Cover Categories in ÄrlaclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jul 657%Jul 657%Nov 2623%Nov 2623%Apr 439%Apr 439%Oct 540%Oct 540%NowNowclearmostly clearpartly cloudymostly cloudyovercast
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.
FractionJanFebMarAprMayJunJulAugSepOctNovDec
Cloudier 74%74%66%58%49%45%45%48%52%67%76%75%
Clearer 26%26%34%42%51%55%55%52%48%33%24%25%

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Ärla varies throughout the year.

The wetter season lasts 7.1 months, from May 26 to December 29, with a greater than 25% chance of a given day being a wet day. The month with the most wet days in Ärla is July, with an average of 9.6 days with at least 0.04 inches of precipitation.

The drier season lasts 4.9 months, from December 29 to May 26. The month with the fewest wet days in Ärla is March, with an average of 5.4 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. The month with the most days of rain alone in Ärla is July, with an average of 9.6 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 32% on June 21.

Daily Chance of Precipitation in Ärla

Daily Chance of Precipitation in ÄrlawetdryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jun 2132%Jun 2132%Mar 1417%Mar 1417%Dec 2925%Dec 2925%NowNowsnowrain
The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).
Days ofJanFebMarAprMayJunJulAugSepOctNovDec
Rain 3.2d2.6d3.6d5.5d7.1d9.2d9.6d9.4d8.0d8.3d6.7d4.3d
Mixed 1.4d1.2d1.1d0.5d0.1d0.0d0.0d0.0d0.0d0.2d0.9d1.5d
Snow 2.0d1.8d0.8d0.2d0.0d0.0d0.0d0.0d0.0d0.1d0.7d1.9d
Any 6.6d5.6d5.4d6.2d7.3d9.2d9.6d9.4d8.0d8.6d8.4d7.7d

To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Ärla experiences significant seasonal variation in monthly rainfall.

Rain falls throughout the year in Ärla. The month with the most rain in Ärla is July, with an average rainfall of 2.6 inches.

The month with the least rain in Ärla is February, with an average rainfall of 0.5 inches.

Average Monthly Rainfall in Ärla

Average Monthly Rainfall in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in1 in1 in2 in2 in3 in3 in4 in4 in5 in5 inJul 92.7 inJul 92.7 inFeb 130.5 inFeb 130.5 inNowNow
The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average snowfall.
JanFebMarAprMayJunJulAugSepOctNovDec
Rainfall 0.6″0.5″0.7″1.2″1.6″2.4″2.6″2.3″2.0″1.8″1.5″0.9″

Snowfall

As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Ärla experiences significant seasonal variation in monthly snowfall.

The snowy period of the year lasts for 5.3 months, from November 1 to April 10, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Ärla is January, with an average snowfall of 4.7 inches.

The snowless period of the year lasts for 6.7 months, from April 10 to November 1. The least snow falls around July 24, with an average total accumulation of 0.0 inches.

Average Monthly Snowfall in Ärla

Average Monthly Snowfall in ÄrlasnowsnowJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in2 in2 in4 in4 in6 in6 in8 in8 in10 in10 in12 in12 inJan 244.9 inJan 244.9 inJul 240.0 inJul 240.0 inNov 11.0 inNov 11.0 inApr 101.0 inApr 101.0 in
The average snowfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average rainfall.
JanFebMarAprMayJunJulAugSepOctNovDec
Snowfall 4.7″4.1″2.0″0.8″0.1″0.0″0.0″0.0″0.0″0.2″2.2″4.6″

The length of the day in Ärla varies extremely over the course of the year. In 2024, the shortest day is December 21, with 6 hours, 6 minutes of daylight; the longest day is June 20, with 18 hours, 36 minutes of daylight.

Hours of Daylight and Twilight in Ärla

Hours of Daylight and Twilight in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 9 minMar 2012 hr, 9 minMar 2018 hr, 36 minJun 2018 hr, 36 minJun 2012 hr, 13 minSep 2212 hr, 13 minSep 226 hr, 6 minDec 216 hr, 6 minDec 21nightnightdayNowNow
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.
Hours ofJanFebMarAprMayJunJulAugSepOctNovDec
Daylight 7.0h9.3h11.9h14.6h17.1h18.5h17.7h15.4h12.8h10.1h7.7h6.2h

The earliest sunrise is at 3:36 AM on June 18, and the latest sunrise is 5 hours, 13 minutes later at 8:50 AM on December 27. The earliest sunset is at 2:52 PM on December 15, and the latest sunset is 7 hours, 21 minutes later at 10:13 PM on June 23.

Daylight saving time (DST) is observed in Ärla during 2024, starting in the spring on March 31, lasting 6.9 months, and ending in the fall on October 27.

Sunrise & Sunset with Twilight and Daylight Saving Time in Ärla

Sunrise & Sunset with Twilight and Daylight Saving Time in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 183:36 AMJun 183:36 AM10:13 PMJun 2310:13 PMJun 23Dec 152:52 PMDec 152:52 PM8:50 AMDec 278:50 AMDec 27Mar 31DSTMar 31DSTDSTOct 27DSTOct 27daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
The solar day over the course of the year 2024. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray. The transitions to and from daylight saving time are indicated by the 'DST' labels.

The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation.

Solar Elevation and Azimuth in Ärla

Solar Elevation and Azimuth in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AM00001010202030304040500001010101020203030404050754NowNow
northeastsouthwest
Solar elevation and azimuth over the course of the year 2024. The black lines are lines of constant solar elevation (the angle of the sun above the horizon, in degrees). The background color fills indicate the azimuth (the compass bearing) of the sun. The lightly tinted areas at the boundaries of the cardinal compass points indicate the implied intermediate directions (northeast, southeast, southwest, and northwest).

The figure below presents a compact representation of key lunar data for 2024. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases.

Moon Rise, Set & Phases in Ärla

The time in which the moon is above the horizon (light blue area), with new moons (dark gray lines) and full moons (blue lines) indicated. The shaded overlays indicate night and civil twilight.

We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.

The perceived humidity level in Ärla, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.

Humidity Comfort Levels in Ärla

Humidity Comfort Levels in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jan 290%Jan 290%Jul 291%Jul 291%NowNowdrydrycomfortablecomfortablehumidhumid
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.
JanFebMarAprMayJunJulAugSepOctNovDec
Muggy days 0.0d0.0d0.0d0.0d0.0d0.0d0.2d0.2d0.0d0.0d0.0d0.0d

This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.

The average hourly wind speed in Ärla does not vary significantly over the course of the year, remaining within 0.4 miles per hour of 5.4 miles per hour throughout.

Average Wind Speed in Ärla

Average Wind Speed in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph1 mph1 mph2 mph2 mph3 mph3 mph4 mph4 mph5 mph5 mph6 mph6 mph7 mph7 mph8 mph8 mph9 mph9 mphJan 25.9 mphJan 25.9 mphJul 185.0 mphJul 185.0 mphNowNow
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Wind Speed (mph) 5.85.55.65.55.45.25.05.35.75.75.65.7

The predominant average hourly wind direction in Ärla varies throughout the year.

The wind is most often from the south for 1.3 months, from April 17 to May 27, with a peak percentage of 31% on May 9. The wind is most often from the west for 11 months, from May 27 to April 17, with a peak percentage of 42% on January 1.

Wind Direction in Ärla

Wind Direction in ÄrlaWSWJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwestsoutheastnorth
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Ärla is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.

The average water temperature experiences significant seasonal variation over the course of the year.

The time of year with warmer water lasts for 2.6 months, from June 27 to September 14, with an average temperature above 57°F. The month of the year in Ärla with the warmest water is August, with an average temperature of 62°F.

The time of year with cooler water lasts for 4.6 months, from December 10 to April 29, with an average temperature below 40°F. The month of the year in Ärla with the coolest water is February, with an average temperature of 35°F.

Average Water Temperature in Ärla

Average Water Temperature in ÄrlawarmcoolcoolJanFebMarAprMayJunJulAugSepOctNovDec25°F25°F30°F30°F35°F35°F40°F40°F45°F45°F50°F50°F55°F55°F60°F60°F65°F65°F70°F70°FAug 563°FAug 563°F34°FFeb 2834°FFeb 28Jun 2757°FJun 2757°FSep 1457°FSep 1457°FDec 1040°FDec 1040°FApr 2940°FApr 2940°FNowNow
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 36°F35°F35°F38°F45°F54°F61°F62°F57°F50°F44°F39°F

To characterize how pleasant the weather is in Ärla throughout the year, we compute two travel scores.

The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit Ärla for general outdoor tourist activities is from late June to mid August, with a peak score in the third week of July.

Tourism Score in Ärla

Tourism Score in Ärlabest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.66.60.00.0NowNowtemperaturetemperature cloudscloudsprecipitationprecipitationtourism score
The tourism score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit Ärla for hot-weather activities is from mid July to early August, with a peak score in the third week of July.

Beach/Pool Score in Ärla

Beach/Pool Score in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec002244668810103.13.10.00.0NowNowtemperaturetemperature cloudscloudsprecipitationprecipitation
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Methodology

For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.

Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.

Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.

Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.

Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.

Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).

The growing season in Ärla typically lasts for 4.8 months (148 days), from around May 5 to around September 30, rarely starting before April 17 or after May 24, and rarely ending before September 13 or after October 21.

Time Spent in Various Temperature Bands and the Growing Season in Ärla

Time Spent in Various Temperature Bands and the Growing Season in Ärlagrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%May 550%May 550%Sep 3050%Sep 3050%May 2490%May 2490%Sep 1390%Sep 1390%Apr 1710%Apr 1710%Oct 2110%Oct 2110%0%Dec 150%Dec 15Jul 21100%Jul 21100%NowNowfrigidfreezingvery coldcoldcoolcomfortablewarm
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.

Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.

Based on growing degree days alone, the first spring blooms in Ärla should appear around May 15, only rarely appearing before May 5 or after May 27.

Growing Degree Days in Ärla

Growing Degree Days in ÄrlaJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F200°F200°F400°F400°F600°F600°F800°F800°F1,000°F1,000°F1,200°F1,200°F1,400°F1,400°FMay 1590°FMay 1590°FAug 3900°FAug 3900°FDec 311,372°FDec 311,372°F
The average growing degree days accumulated over the course of the year, with 25th to 75th and 10th to 90th percentile bands.

This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.

The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year.

The brighter period of the year lasts for 3.2 months, from May 3 to August 9, with an average daily incident shortwave energy per square meter above 5.0 kWh. The brightest month of the year in Ärla is June, with an average of 6.1 kWh.

The darker period of the year lasts for 4.4 months, from October 15 to February 26, with an average daily incident shortwave energy per square meter below 1.4 kWh. The darkest month of the year in Ärla is December, with an average of 0.2 kWh.

Average Daily Incident Shortwave Solar Energy in Ärla

Average Daily Incident Shortwave Solar Energy in ÄrlabrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJun 206.1 kWhJun 206.1 kWhDec 190.2 kWhDec 190.2 kWhMay 35.0 kWhMay 35.0 kWhAug 95.0 kWhAug 95.0 kWhOct 151.4 kWhOct 151.4 kWhFeb 261.4 kWhFeb 261.4 kWhNowNow
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Solar Energy (kWh) 0.41.02.33.95.56.15.84.63.01.40.50.2

For the purposes of this report, the geographical coordinates of Ärla are 59.280 deg latitude, 16.679 deg longitude, and 164 ft elevation.

The topography within 2 miles of Ärla contains only modest variations in elevation, with a maximum elevation change of 194 feet and an average elevation above sea level of 186 feet. Within 10 miles also contains only modest variations in elevation (358 feet). Within 50 miles contains only modest variations in elevation (702 feet).

The area within 2 miles of Ärla is covered by trees (65%) and cropland (31%), within 10 miles by trees (61%) and cropland (29%), and within 50 miles by trees (52%) and cropland (26%).

This report illustrates the typical weather in Ärla, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.

Temperature and Dew Point

There are 5 weather stations near enough to contribute to our estimation of the temperature and dew point in Ärla.

For each station, the records are corrected for the elevation difference between that station and Ärla according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.

The estimated value at Ärla is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Ärla and a given station.

The stations contributing to this reconstruction are:

To get a sense of how much these sources agree with each other, you can view a comparison of Ärla and the stations that contribute to our estimates of its temperature history and climate. Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data.

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus.

All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.

Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.

Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.

Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .

Time zones for airports and weather stations are provided by AskGeo.com .

Maps are © OpenStreetMap contributors.

Disclaimer

The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.

We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands.

We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader.

Please review our full terms contained on our Terms of Service page.